/Engine/Source/Runtime/ApplicationCore/Public/GenericPlatform/Accessibility/GenericAccessibleInterfaces.h
If the current widget has no previous sibling, we return the parent of the current widget.
The logical previous widget in the accessible widget hierarchy.
[TSharedPtr](API\Runtime\Core\Templates\TSharedPtr)< [IAccessibleWidget](API\Runtime\ApplicationCore\GenericPlatform\Accessibility\IAccessibleWidget) > GetPreviousWidgetInHierarchy()